Toyota and the other petrol-engined LMP1 prototypes have been handed a performance break ahead of the Le Mans 24 Hours next month.
Petrol-powered P1s have been granted an extra three litres of fuel capacity by the FIA endurance committee, which brings the Toyota TS030 HYBRID up 76 litres and non-hybrids entries such as Rebellion Racing's Lola-Toyota B12/60s up to 78 litres.
The move follows the domination of the opening two rounds of the World Endurance Championship by the turbodiesel Audi R18 e-tron quattro, which has not been affected by the latest Balance of Performance changes.
Toyota argued in the wake of this month's Spa round that Audi has been able to turn the fuel consumption advantage it enjoyed last year into horsepower.
Pascal Vasselon, Toyota Motorsport GmbH's technical director, said that it had been a mistake to only adjust the size of the engine air-restrictors over the winter.
There have also been minor changes to the Balance of Performance in the GTE Pro class for Le Mans: the Aston Martin Vantage GTE has had its minimum weight raised by 10kg and the new Porsche 911 RSR has been granted a larger restrictor.